| The epidemiological analysis of swine fever in Suckling sows,reserve sows,piglets and fattening sows was carried out in a large-scale pig farm in changchun,jilin province.Combined with the monitoring of the antibody level of CSFV in a large-scale pig farm,the antibody level differences of piglets under different immunization procedures and the fluctuation and growth rules of maternal antibodies of piglets,a comprehensive prevention and control proposal and countermeasures suitable for CSFV in this pig farm were worked out,and the application was promoted in the pig farm.Monitoring of serum antibody level of CSFV: an on-site investigation was conducted on a large-scale pig farm.Blood samples were collected randomly from pigs at different growth stages of the pig farm under investigation,and the CSFV ELISA test was used to detect the antigen of CSFV.No negative cases were found in the pig herd of the pig farm,and the immune effect was good.The antibody of pregnant sows had the highest blocking effect(68%).The positive and effective blocking of fattening pigs were 45%.The effective blocking rate of Suckling sows was relatively reduced.Suckling piglets were found to have maternal antibodies,with an effective blocking rate of 56%.The stable production and sustainable development of large-scale pig farm is based on the stability of the breeding pig herd(reserve sows,pregnant sows and lactating sows)of the pig farm.The control situation of swine fever in the pig farm is directly related to the health status of the whole pig herd.Piglets swine fever rules of maternal antibody typical in the study: piglet birth stepmother source antibody level is higher,before the age of 30,maternal antibody levels remain in which critical value by more than 80%,antibody levels started to reduce after 30 days of age,the antibody levels drop rate increased with the increase of age,when 50 days of age,the antibody level of piglets is down to 5%.In this experiment,piglets were set to be weaned at the age of 25 days,so the decline rate of maternal antibody level was accelerated after the age of 25 days,and the absorption of antibodies from the maternal source was weakened.In view of the current situation of pig farms,if piglets do not adopt advanced immunization,25-30 days is a better immunization time for CSFV.Effect of different immunization procedures on the antibody level of swine fever: piglets in group I were injected with 1 dose of rabbit attenuated vaccine of swine fever at 0 and 40 days of age,respectively,in the advanced immunization group;piglets in group II were injected with 1 dose of rabbit attenuated vaccine of swine fever at 25 and 60 days of age,respectively,in the normal immunization group.The immunization procedures for other vaccines remain unchanged.With the increase of piglets' age,the antibody level of CSFV in group I showed a gradually increasing trend,and the average blocking rate of 130 days was as high as 66.4%,which was positive.The antibody level of piglets in the test group II showed a gradually increasing trend before 80 days of age,but gradually decreased after 100 days of age,but the positive rate of blocking the antibody against CSFV reached 100%,indicating that the two immune programs could meet the requirements of preventing CSFV in the pig farm,and group I was superior to group II.According to the epidemiological investigation results of a large-scale pig farm in this paper,Suggestions and countermeasures for the comprehensive prevention and control of atypical swine fever in the pig farm were formulated according to the actual situation of the pig farm,so as to improve the prevention and control of swine fever in the pig farm.This paper can provide theoretical basis for the prevention and control of atypical swine fever in pig production practice,and provide reference for the control and prevention of swine fever. |
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